Mucinous cystic neoplasms of the liver with biliary prolapse.

OBJECTIVES: To describe the prevalence, clinical and radiological findings of biliary prolapse in pathologically proven mucinous cystic neoplasm of the liver (MCN-L). METHODS: Thirty-four patients, all female with median age 50 years (range, 14-82), with histologically confirmed MCN-L were enrolled. Median tumor size was 9 cm (range, 2-21 cm). Fifty-seven examinations (17 ultrasound, 25 CT, and 15 MR) among 34 MCN-Ls were reviewed. Two radiologists retrospectively assessed images for tumor location, size and other morphological features of the tumor, presence of biliary prolapse and upstream bile duct dilatation. Ultrasound, CT, and MR were assessed separately. Clinical features were evaluated. Clinical and radiological characteristics of MCN-L with and without biliary prolapse were compared. RESULTS: 15% (5/34) of MCN-Ls showed biliary prolapse confirmed at pathology. None of MCN-Ls were associated with invasive carcinoma. Patients with biliary prolapse were significantly younger than those without (median 27 years [22-56] vs. median 51 years [14-82], p = 0.03). MCN-Ls with biliary prolapse were significantly smaller than those without (median 6.4 cm [2.2-7.5] vs. median 9.6 cm [3.1-21], p = 0.01). The upstream bile duct was dilated more frequently in MCN-Ls with biliary prolapse (100% vs. 38%, p = 0.02). Jaundice was significantly more common in MCN-Ls with biliary prolapse (80 vs 3%, p = 0.0005). Other clinical or radiological features were not significantly different between two groups. CONCLUSIONS: Biliary prolapse was found in 15% of MCN-Ls. MCN-Ls with biliary prolapse were significantly smaller and were more commonly associated with upstream bile duct dilation and jaundice than those without biliary prolapse.